/Engine/Plugins/VirtualProduction/Rivermax/RivermaxCore/Source/RivermaxCore/Public/IRivermaxOutputStream.h
Tries to reserve a frame for the next capture If FRivermaxOutputStreamOptions::EFrameLockingMode equals BlockOnReservation, this method will block until a free frame is found.
bool ReserveFrame ( uint32 FrameIdentifier ) const